The influence exerted by some acetylenic alcohols (1-octyne-3-ol, OCT; 3-methyl-1-butyne-3-ol, H; 1-iodo-3-methyl-1-butyne-3-ol, I) towards chromium corrosion in 1N HCl solution at 70 °C has been evaluated by EIS measurements and polarization curve recordings.
These compounds are poor inhibitors of chromium acid dissolution, despite the positive results obtained on other transition metals such as iron or nickel.
Only OCT, at 10 mM concentration, shows an high protective action, which, however, decreases rapidly during the first two hours of testing.
Even the addition of chromium to iron alloys is detrimental to the inhibitive behaviour of these additives; for instance, the protective action of OCT is high and persistent only in the case of plain steel, whereas it decreases rapidly in the case of chromium-containing steels.
The negative influence of dissolved Cr3+ ions has also been ascertained, as their presence causes a reduction in the inhibiting efficiency of OCT, on both plain steel and chromium-containing steels.

The influence exerted by some acetylenic alcohols (1-octyne-3-ol, OCT; 3-methyl-1-butyne-3-ol, H; 1-iodo-3-methyl-1-butyne-3-ol, I) towards chromium corrosion in 1N HCl solution at 70 °C has been evaluated by EIS measurements and polarization curve recordings.
These compounds are poor inhibitors of chromium acid dissolution, despite the positive results obtained on other transition metals such as iron or nickel.
Only OCT, at 10 mM concentration, shows an high protective action, which, however, decreases rapidly during the first two hours of testing.
Even the addition of chromium to iron alloys is detrimental to the inhibitive behaviour of these additives; for instance, the protective action of OCT is high and persistent only in the case of plain steel, whereas it decreases rapidly in the case of chromium-containing steels.
The negative influence of dissolved Cr3+ ions has also been ascertained, as their presence causes a reduction in the inhibiting efficiency of OCT, on both plain steel and chromium-containing steels.